Pool Chemical Calculator
Free exact dosing — chlorine, pH, alkalinity, shock & CYA
▾
Free exact dosing — chlorine, pH, alkalinity, shock & CYA
Every certified pool technician knows chemistry only works in the correct sequence. CDC & PHTA recommend this order:
Select pool size and problem for instant dosing — no deep knowledge needed.
Step 1 — My pool is approximately:⚠️ Please select a pool size first.
Your dosing plan:
Starting-point estimates. Test after each addition. Use the Full Calculator below for exact dosing.
Advertisement
Pool Volume Calculator
Enter dimensions to calculate exact volume. Auto-fills all calculators.
Same as shallow if flat-bottomed
✓ Volume saved — switch tabs to calculate doses
Chlorine Calculator
CDC recommends 1–3 ppm free chlorine. With CYA, maintain at least 2 ppm. Always balance pH first.
CDC pools: 1–3 ppm · hot tubs: 3–5 ppm
pH Calculator
At pH 8.0, chlorine is only 21% as effective as pH 7.4. PHTA/CDC: 7.2–7.6. Adjust alkalinity before pH.
PHTA/CDC: 7.2–7.6
Total Alkalinity Calculator
Total alkalinity anchors your pH. NSPF recommends 80–120 ppm. Fix alkalinity first — pH often corrects itself.
NSPF ideal: 80–120 ppm
Pool Shock Calculator
NSPF recommends at least 10 ppm. Green pools: 20–30 ppm. Shock at dusk. No swimming until FC < 4 ppm.
Standard: 10 ppm · Green pool: 20–30 ppm
CYA / Stabilizer Calculator
CYA protects chlorine from UV — without it, sunlight destroys ~75% of chlorine within 2 hrs. CDC/PHTA: 30–50 ppm outdoors. Above 80 ppm, CYA impairs chlorine effectiveness.
Chlorine pools: 30–50 ppm
Salt Level Calculator
Most salt chlorine generators (SWGs) require 2700–3400 ppm. Check your generator manual for exact target. Always use pool-grade sodium chloride — not table salt or rock salt.
Most SWGs: 2700–3400 ppm. Check your manual.
Ideal Pool Chemistry — CDC & PHTA Standards
Sources: CDC Healthy Swimming, PHTA, NSPF Pool & Spa Operator Handbook
Advertisement
Pool Chemicals & Testing
Products used with this calculator — via Amazon
Taylor K-2006C Professional Pool Test Kit
Gold standard in pool testing. FAS-DPD titration for precise chlorine, pH & alkalinity. Used by certified pool operators.
View on Amazon →
In The Swim 3" Chlorine Tablets — 50 lbs
Top-selling slow-dissolving trichlor. 90% available chlorine, UV-protected, individually wrapped. Works in all feeders.
View on Amazon →
Clorox Pool & Spa Chlorine Stabilizer 4LB
100% cyanuric acid stabilizer. Protects chlorine from UV degradation. Compatible with all pool types including salt water.
View on Amazon →
In The Swim Pool Opening Chemical Kit
Complete season start-up bundle. Shock, algaecide, clarifier and more. Pre-measured for up to 15,000 gallons.
View on Amazon →🤖 Pool Cleaning Robots
Best-reviewed automatic pool cleaners — via Amazon
Dolphin Nautilus CC Plus Wi-Fi — Inground up to 40 FT
Best-seller for inground pools. Wall climbing, top-load filter, Wi-Fi scheduling. Plug & play, 2-hour clean cycle.
View on Amazon →
Dolphin Premier Robotic Pool Cleaner — Inground up to 50 FT
Premium inground cleaner. Dual motors, triple filtration, weekly timer. Cleans floor, walls & waterline.
View on Amazon →
Dolphin Nautilus CC — Inground up to 33 FT
Top-rated budget inground robot. Wall climbing, active scrubber brush, top-load filter. Great for smaller inground pools.
View on Amazon →
Beatbot AquaSense 2 Pro Cordless Pool Cleaner
High-end cordless robot. 5-in-1 cleaning — floor, walls, waterline, surface skimming and water clarification. App control.
View on Amazon →Advertisement
This free pool chemical calculator covers both chlorine pools and salt water pools (SWG systems). All dosing formulas are sourced from the National Swimming Pool Foundation (NSPF) Pool & Spa Operator Handbook, CDC Healthy Swimming guidelines, and the Pool & Hot Tub Alliance (PHTA). Available in English, Spanish, Portuguese, French and Chinese with Imperial and Metric units.
Salt water pools use a salt chlorine generator (SWG) to produce chlorine from dissolved salt — they still require chlorine-level maintenance, just from a different source. Key differences: salt pools need CYA at 60–80 ppm (higher than the 30–50 ppm for chlorine pools), pH tends to drift upward more frequently, and the target salt level is typically 2700–3400 ppm depending on your generator manufacturer.
At pH 7.2, approximately 63% of free chlorine exists as hypochlorous acid — the active sanitising molecule. At pH 8.0, that drops to 21%, meaning three times as much chlorine is needed for the same sanitation. The CDC recommends 7.0–7.8, with 7.4–7.6 as the ideal range.
Pool Chemical Calculator
Free exact dosing — chlorine, pH, alkalinity, shock & CYA